This patient should receive conversion chemotherapy for his currently unresectable tumor. Conversion chemotherapy is given for the purpose of shrinking a tumor that is unresectable usually due to its location, often because of proximity to significant vascular structures as in this patient. Through shrinkage of the tumor with conversion chemotherapy, an adequate plane of resection between the tumor and the middle hepatic vein may become available, allowing complete removal of the tumor. This is particularly important in this patient with localized metastatic colon cancer. Although metastatic colorectal cancer is generally considered treatable but not curable, some patients with metastatic disease confined to a single organ (usually the liver or lung) may be amenable to surgical resection, and complete removal of all gross disease may be curative. Patients with a limited number of liver-only lesions, such as this patient, have been reported to have long-term disease-free survival rates of 25% to 50%.

Adjuvant chemotherapy is the term used for treatment given after resection of a tumor is performed with curative intent. The purpose of adjuvant chemotherapy is to eradicate any residual microscopic metastatic disease that might still be present outside of the surgical field. Adjuvant chemotherapy would not be possible in this patient with currently unresectable disease.

Neoadjuvant chemotherapy is similar to adjuvant chemotherapy in that it is given in the setting of curative-intent surgery; however, neoadjuvant therapy is given before surgery in an attempt to eradicate any unseen micrometastases that might be present outside of the surgical field. Although neoadjuvant chemotherapy may have the effect of tumor shrinkage, it differs from conversion chemotherapy in that it is given in patients who have resectable disease preoperatively.

Palliative chemotherapy is given to a patient with incurable, unresectable cancer and is given without realistic curative intent. Palliative chemotherapy may be administered for the purposes of possibly prolonging survival and/or controlling tumor-related symptoms.

Because chemotherapy may increase the opportunity for cure in this clinical setting, it would be inappropriate to not offer this treatment option.